Field of the Invention
This invention relates to compositions and methods for removing oily soils from fabrics. More particularly, the invention relates to the use of specific mixtures of water-insoluble solvents and solvent soluble emulsifiers in aqueous washing media followed by treatment with a composition incorporating a surface active agent (surfactant) to remove residual solvent from the fabrics.
Current laundry products and procedures exhibit one or more deficiencies when used to clean oil stains, particularly hydrocarbon stains, from fabrics. Fatty triglyceride soils, especially those arising from natural body secretions, present another type of oily stain which is difficult to remove from modern fabrics by means of simple aqueous laundering processes. Such deficiencies are especially apparent when polyester or polyester-cotton fabric blends soiled with various oily materials are laundered in aqueous laundry baths.
Heretofore, effective oil removal from modern fabrics has largely been accomplished by means of relatively inconvenient and expensive methods involving non-aqueous dry cleaning processes. Another approach for removal of oily stains has been pretreatment of soiled areas of fabrics with liquid detergents or specific pretreatment compositions prior to normal laundering. This approach has not proven entirely satisfactory. It is not always practical to identify the fabric areas which need special attention prior to laundering. Results are often disappointing. Accordingly, compositions and methods which would provide economical and efficient removal of oily soils from fabrics employing conventional household laundry equipment are desirable.
The present invention employs a sequential treatment of fabrics in an aqueous washing medium with first, a water-insoluble solvent containing about 3% to about 30% of a solvent soluble water-in-oil emulsifier typically having an hydrophilic lipophilic balance (HLB) value of from about 2 to about 12, and second, a composition comprising a water soluble surfactant typically having an HLB value of from about 11 to about 18.